The present invention relates to an arrangement for the detachable fixing of an inlet device to the cylinder head of an internal combustion engine by means of a locking mechanism which is integrated at least in a flange intrinsic to the cylinder head.
Such an arrangement is known from DE 40 35 016 A1. The inlet device there has a connecting end made of a rubber-elastic material, said connecting end being slipped over the flange of the cylinder head. However, since this is a loose connection which is not sealed and does not hold when the engine is running, in the known arrangement a clamping ring made of a relatively rigid material is pushed over the connecting end, the inner diameter of the clamping ring having a lower value than the outer diameter of the connecting end, with the result that this procedure requires a certain amount of skill and expenditure of force as well as a certain amount of time. In addition, while this fixing method is possibly well suited for a hand-operated tool, since the cylinder head flange is easily accessible there, the method is not satisfactory for applying under the confined conditions in the engine compartment of a motor vehicle. Furthermore, two fixing steps, for which moreover two hands are needed, have to be carried out in the known method.
A locking mechanism is disclosed in DE 196 47 184 A1, wherein a rotating movement of a clamp spring is executed in order to fix an air inlet tube in a housing section, but the housing section itself is connected by means of a conventional screw connection to the cylinder head of an internal combustion engine.
The detachable connection of such inlet devices to the cylinder head by means of connector elements such as screws, threaded bolts or spring clips, as described in DE 196 47 184 A1, is the customary connecting method. The design, manufacture and assembly of such connector elements entail a corresponding outlay. In addition, the accessibility of the fixing elements presents a substantial problem, particularly in the case of complex inlet devices.
The object of the present invention is to create an arrangement for the detachable fixing of an inlet device to the cylinder head of an internal combustion engine, said arrangement being as simple as possible to assemble and eliminating the problem of the accessibility of connector elements.
To achieve this object, the invention provides that in an arrangement of this type the locking mechanism, which is also integrated in a flange of the inlet device, can be snapped in by a rotating movement of the inlet device relative to the cylinder head.
In one embodiment an arrangement for the detachable fixing of an inlet device to the cylinder head of an internal combustion engine comprises means of a locking mechanism which is integrated at least into one intrinsic flange of the cylinder head, wherein the locking mechanism, also integrated into a flange of the inlet device, can be snapped in through a rotating movement of the inlet device relative to the cylinder head.
The flange of the inlet device can be inserted on one side into an appropriately sized undercut clamping notch of the cylinder head and can be secured on the opposite side by a snap-in notch/spring connection on the cylinder head. The snap-in notch/spring connection may consist of a sprung section formed on the inlet device and an undercut snap-in notch formed on the cylinder head, into which snap-in notch the sprung section with a shoulder molded thereon can be snapped in. A ramp can be molded on the sprung section, said ramp providing for the deflection of the sprung section, said deflection being necessary in order for the locking mechanism to snap in. The sprung section may have a projecting actuating end for detaching the snap-in notch/spring connection. Between adjacent faces of the cylinder head and of the inlet device an elastic seal may be located, and said seal may pre-bias the locking mechanism into a state free from play.
Another embodiment is an arrangement for the detachable fixing of an inlet device to the cylinder head of an internal combustion engine wherein the inlet device can be fixed to the cylinder head by means of a locking mechanism, the locking mechanism is integrated into a flange of the inlet device and into an intrinsic flange of the cylinder head, the locking mechanism can be snapped in by means of a rotating movement of the inlet device relative to the cylinder head, and the flange of the inlet device can on one side be inserted into an appropriately sized undercut clamping notch of the cylinder head and on the opposite side be secured by a snap-in notch/spring connection to the cylinder head.
Yet another embodiment is an arrangement for the detachable fixing of an inlet device to the cylinder head of an internal combustion engine comprising a locking mechanism operable to fix the inlet device to the cylinder head, wherein the locking mechanism is integrated into a flange of the inlet device and into an intrinsic flange of the cylinder head, the locking mechanism comprises snap-in means operable to snap in by a rotating movement of the inlet device relative to the cylinder head, the cylinder head comprises an undercut clamping notch, and further comprising a snap-in notch/spring connection.
The snap-in notch/spring connection may consist of a sprung section formed on the inlet device and an undercut snap-in notch formed on the cylinder head, into which snap-in notch the sprung section with a shoulder molded thereon can be snapped in. A ramp can be molded on the sprung section, said ramp providing for the deflection of the sprung section, said deflection being necessary in order for the locking mechanism to snap in. The sprung section may have a projecting actuating end for detaching the snap-in notch/spring connection. Between adjacent faces of the cylinder head and of the inlet device an elastic seal may be located, and said seal may pre-bias the locking mechanism into a state free from play.
Consequently, no separate connector elements are required in the solution according to the invention. This gives rise to an extremely simple assembly, since, in order to attach and detach the inlet device, no connector elements have to be tightened or loosened. Furthermore, since the problem of accessibility in relation to connector elements does not arise, there is increased freedom of design in respect of the suction device.